Ball-caster



Patented Dec. 6, |898.

A H COBB BALL CASTER.

(Application filed Mar. 20, 1897 (rio Model.)

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UNITED STATES PATENT Errea.

ALPI-IONSOII. COBB, OF ASHEVILL, NORTH CAROLINA.

BALL-CASTER.

SPECIFICATION forming part of Letters Patent No. 615,529, dated December6, 1898.

Application filed 'Mal'oh 20, 1 8 9 7.

Serial No. 628,465. (No model.)

To au whom it may concern:

Be it known that I, ALPHONSO II. COBB, residing at Asheville,in thecounty of Buncombe and State of North Carolina, have invented bodyhaving an integral inwardly-projecting iiange surrounding its outlet anda central l stud being provided between the plurality of balls. Fig. 2is a bottom plan view of such construction. Fig. 3 is a sectional viewshowing the body provided with a lcentral stud, the iiange or rib beingomitted. Fig. 4shows a somewhat different construction in which thecentral stud is omitted and the balls are retained by the flangesurrounding the outlet of the socket in the holder, and Fig. 5 is adetail diagrammatic view.

In carrying out my invention I provide a body or holder A, which has asocket B, fitted to receive a plurality of balls side by side in suchmanner that said balls will protrude from the outlet of said socket andso form an antifriction-bearing to roll upon the iioor or other support.By plurality of balls I mean two or more, preferably three, as shown,and in order to retain said balls in the socket I provide means by whichto contract or reduce the area of the outlet of socket B. This may beeffected by means of an inwardly-projecting lian ge surrounding themouth of said outlet, as shown at C in Fig. 1 and at D in Fig. 4, or itmay be effected by means of the head e of a stud E, passed centrallybetween the balls and secured by threading or otherwise to the body, asshown in Fig. 3. It will also be understood that for greater security acentral headed stud may be supplied to the construction shown in Fig. 4and that to provide for greater play of the balls a iange may besupplied, as shown in connection with the stud in Fig. l, and thisconstruction shown roof may be fiat or of other form.

in Fig. l may for some reasons be preferred and will now be describedmore in detail. In the said construction the socket B has its roof orupper wall concaved, and such construction is preferred, but wheredesired the y The three balls F fit in the socket and are retained bythe headed stud, the head of which serves as a means for reducing orcontracting the area of the outlet from the socket and so serves toretain the balls in the body. Instead of reducing the area at the centerby means of the stud it may be reduced at its circumference by means ofthe flange shown in Fig. 4, or, as before suggested, the area may bereduced by means of both the central stud and the circumferentialiiange.

In the construction shown in Fig. 1 I prefer in practice to make thecasting in one piece, with the exterior opening or voutlet of its socketof just sufficient size to admitthe balls when the central stud isremoved, the inner diameter of said socket above its out let beinglarger than the outlet, so the balls may have a slight play when thestud is entered in position to lock themv in place.

In wooden table-legs and the like the in vention may be practiced bysuitably forming the socket B in the ends of said legs, as will bereadily understood.

In operation the bed, stand, or other article supplied with my castersbeing moved in any.

direction two of the balls will fall as soon as motion begins to therear until they bring up upon the outer rim of the cavity or socket,when friction will begin, which can only be that exercised upon thewalls, as per the dia gram, Fig. 5, showing resolution of forces. Thethird ball works loosely because of space in front and overhead.

In practice the balls have a rotary elfectas, for instance, if thecaster is tipped slightly the balls will roll about the circumference,that is if the stem which enters the bed-post is at a slight angle tothe perpendicular.

Having thus described my invention, what I claim, and desire to secureby Letters Pat ent, isn

1. A caster composed of a body or holder having a socket and provided atthe lower end thereof with an inwardly-projected iiange the ballsfitting in said socket and the stud IOO passed between said balls andhaving a head overlapping the same substantially as shown and described.

2. A caster composed of a body or holder,

Aa plurality of balls fitted in and protruding mouth of the holder and apin or stud passed between andhaving a head overlapping the said ballssubstantially as described.

4. A caster composed of the holder having a socket, a plurality of ballsin said socket in contact with each other and protruding from the socketto bear .against` the floor or support, and means common to all saidballs whereby to retain them in the socket of the holder substantiallyas described.

ALPHONSO H. COBB.

Witnesses:

GEO. F. SCOTT, JOHN A. WAGNER..

